Commit Graph

947 Commits

Author SHA1 Message Date
David Ahern
cff6a327d7 ipv6: Fix unbalanced rcu locking in rt6_update_exception_stamp_rt
The nexthop path in rt6_update_exception_stamp_rt needs to call
rcu_read_unlock if it fails to find a fib6_nh match rather than
just returning.

Fixes: e659ba31d8 ("ipv6: Handle all fib6_nh in a nexthop in exception handling")
Signed-off-by: David Ahern <dsahern@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2019-08-05 13:16:58 -07:00
Linus Torvalds
5f4fc6d440 Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net
Pull networking fixes from David Miller:

 1) Fix AF_XDP cq entry leak, from Ilya Maximets.

 2) Fix handling of PHY power-down on RTL8411B, from Heiner Kallweit.

 3) Add some new PCI IDs to iwlwifi, from Ihab Zhaika.

 4) Fix handling of neigh timers wrt. entries added by userspace, from
    Lorenzo Bianconi.

 5) Various cases of missing of_node_put(), from Nishka Dasgupta.

 6) The new NET_ACT_CT needs to depend upon NF_NAT, from Yue Haibing.

 7) Various RDS layer fixes, from Gerd Rausch.

 8) Fix some more fallout from TCQ_F_CAN_BYPASS generalization, from
    Cong Wang.

 9) Fix FIB source validation checks over loopback, also from Cong Wang.

10) Use promisc for unsupported number of filters, from Justin Chen.

11) Missing sibling route unlink on failure in ipv6, from Ido Schimmel.

* git://git.kernel.org/pub/scm/linux/kernel/git/davem/net: (90 commits)
  tcp: fix tcp_set_congestion_control() use from bpf hook
  ag71xx: fix return value check in ag71xx_probe()
  ag71xx: fix error return code in ag71xx_probe()
  usb: qmi_wwan: add D-Link DWM-222 A2 device ID
  bnxt_en: Fix VNIC accounting when enabling aRFS on 57500 chips.
  net: dsa: sja1105: Fix missing unlock on error in sk_buff()
  gve: replace kfree with kvfree
  selftests/bpf: fix test_xdp_noinline on s390
  selftests/bpf: fix "valid read map access into a read-only array 1" on s390
  net/mlx5: Replace kfree with kvfree
  MAINTAINERS: update netsec driver
  ipv6: Unlink sibling route in case of failure
  liquidio: Replace vmalloc + memset with vzalloc
  udp: Fix typo in net/ipv4/udp.c
  net: bcmgenet: use promisc for unsupported filters
  ipv6: rt6_check should return NULL if 'from' is NULL
  tipc: initialize 'validated' field of received packets
  selftests: add a test case for rp_filter
  fib: relax source validation check for loopback packets
  mlxsw: spectrum: Do not process learned records with a dummy FID
  ...
2019-07-19 10:06:06 -07:00
Matteo Croce
eec4844fae proc/sysctl: add shared variables for range check
In the sysctl code the proc_dointvec_minmax() function is often used to
validate the user supplied value between an allowed range.  This
function uses the extra1 and extra2 members from struct ctl_table as
minimum and maximum allowed value.

On sysctl handler declaration, in every source file there are some
readonly variables containing just an integer which address is assigned
to the extra1 and extra2 members, so the sysctl range is enforced.

The special values 0, 1 and INT_MAX are very often used as range
boundary, leading duplication of variables like zero=0, one=1,
int_max=INT_MAX in different source files:

    $ git grep -E '\.extra[12].*&(zero|one|int_max)' |wc -l
    248

Add a const int array containing the most commonly used values, some
macros to refer more easily to the correct array member, and use them
instead of creating a local one for every object file.

This is the bloat-o-meter output comparing the old and new binary
compiled with the default Fedora config:

    # scripts/bloat-o-meter -d vmlinux.o.old vmlinux.o
    add/remove: 2/2 grow/shrink: 0/2 up/down: 24/-188 (-164)
    Data                                         old     new   delta
    sysctl_vals                                    -      12     +12
    __kstrtab_sysctl_vals                          -      12     +12
    max                                           14      10      -4
    int_max                                       16       -     -16
    one                                           68       -     -68
    zero                                         128      28    -100
    Total: Before=20583249, After=20583085, chg -0.00%

[mcroce@redhat.com: tipc: remove two unused variables]
  Link: http://lkml.kernel.org/r/20190530091952.4108-1-mcroce@redhat.com
[akpm@linux-foundation.org: fix net/ipv6/sysctl_net_ipv6.c]
[arnd@arndb.de: proc/sysctl: make firmware loader table conditional]
  Link: http://lkml.kernel.org/r/20190617130014.1713870-1-arnd@arndb.de
[akpm@linux-foundation.org: fix fs/eventpoll.c]
Link: http://lkml.kernel.org/r/20190430180111.10688-1-mcroce@redhat.com
Signed-off-by: Matteo Croce <mcroce@redhat.com>
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Acked-by: Kees Cook <keescook@chromium.org>
Reviewed-by: Aaron Tomlin <atomlin@redhat.com>
Cc: Matthew Wilcox <willy@infradead.org>
Cc: Stephen Rothwell <sfr@canb.auug.org.au>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2019-07-18 17:08:07 -07:00
David Ahern
49d05fe2c9 ipv6: rt6_check should return NULL if 'from' is NULL
Paul reported that l2tp sessions were broken after the commit referenced
in the Fixes tag. Prior to this commit rt6_check returned NULL if the
rt6_info 'from' was NULL - ie., the dst_entry was disconnected from a FIB
entry. Restore that behavior.

Fixes: 93531c6743 ("net/ipv6: separate handling of FIB entries from dst based routes")
Reported-by: Paul Donohue <linux-kernel@PaulSD.com>
Tested-by: Paul Donohue <linux-kernel@PaulSD.com>
Signed-off-by: David Ahern <dsahern@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2019-07-17 15:25:54 -07:00
Stephen Suryaputra
d8f74f0975 ipv6: Support multipath hashing on inner IP pkts
Make the same support as commit 363887a2cd ("ipv4: Support multipath
hashing on inner IP pkts for GRE tunnel") for outer IPv6. The hashing
considers both IPv4 and IPv6 pkts when they are tunneled by IPv6 GRE.

Signed-off-by: Stephen Suryaputra <ssuryaextr@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2019-07-08 16:37:29 -07:00
Mahesh Bandewar
8d7017fd62 blackhole_netdev: use blackhole_netdev to invalidate dst entries
Use blackhole_netdev instead of 'lo' device with lower MTU when marking
dst "dead".

Signed-off-by: Mahesh Bandewar <maheshb@google.com>
Tested-by: Michael Chan <michael.chan@broadcom.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2019-07-01 19:34:46 -07:00
David S. Miller
d96ff269a0 Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net
The new route handling in ip_mc_finish_output() from 'net' overlapped
with the new support for returning congestion notifications from BPF
programs.

In order to handle this I had to take the dev_loopback_xmit() calls
out of the switch statement.

The aquantia driver conflicts were simple overlapping changes.

Signed-off-by: David S. Miller <davem@davemloft.net>
2019-06-27 21:06:39 -07:00
David Ahern
b2c709cce6 ipv6: Convert gateway validation to use fib6_info
Gateway validation does not need a dst_entry, it only needs the fib
entry to validate the gateway resolution and egress device. So,
convert ip6_nh_lookup_table from ip6_pol_route to fib6_table_lookup
and ip6_route_check_nh to use fib6_lookup over rt6_lookup.

ip6_pol_route is a call to fib6_table_lookup and if successful a call
to fib6_select_path. From there the exception cache is searched for an
entry or a dst_entry is created to return to the caller. The exception
entry is not relevant for gateway validation, so what matters are the
calls to fib6_table_lookup and then fib6_select_path.

Similarly, rt6_lookup can be replaced with a call to fib6_lookup with
RT6_LOOKUP_F_IFACE set in flags. Again, the exception cache search is
not relevant, only the lookup with path selection. The primary difference
in the lookup paths is the use of rt6_select with fib6_lookup versus
rt6_device_match with rt6_lookup. When you remove complexities in the
rt6_select path, e.g.,
1. saddr is not set for gateway validation, so RT6_LOOKUP_F_HAS_SADDR
   is not relevant
2. rt6_check_neigh is not called so that removes the RT6_NUD_FAIL_DO_RR
   return and round-robin logic.

the code paths are believed to be equivalent for the given use case -
validate the gateway and optionally given the device. Furthermore, it
aligns the validation with onlink code path and the lookup path actually
used for rx and tx.

Adjust the users, ip6_route_check_nh_onlink and ip6_route_check_nh to
handle a fib6_info vs a rt6_info when performing validation checks.

Existing selftests fib-onlink-tests.sh and fib_tests.sh are used to
verify the changes.

Signed-off-by: David Ahern <dsahern@gmail.com>
Reviewed-by: Wei Wang <weiwan@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2019-06-27 11:10:23 -07:00
Nicolas Dichtel
2c6b55f45d ipv6: fix neighbour resolution with raw socket
The scenario is the following: the user uses a raw socket to send an ipv6
packet, destinated to a not-connected network, and specify a connected nh.
Here is the corresponding python script to reproduce this scenario:

 import socket
 IPPROTO_RAW = 255
 send_s = socket.socket(socket.AF_INET6, socket.SOCK_RAW, IPPROTO_RAW)
 # scapy
 # p = IPv6(src='fd00💯:1', dst='fd00:200::fa')/ICMPv6EchoRequest()
 # str(p)
 req = b'`\x00\x00\x00\x00\x08:@\xfd\x00\x01\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x01\xfd\x00\x02\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\xfa\x80\x00\x81\xc0\x00\x00\x00\x00'
 send_s.sendto(req, ('fd00:175::2', 0, 0, 0))

fd00:175::/64 is a connected route and fd00:200::fa is not a connected
host.

With this scenario, the kernel starts by sending a NS to resolve
fd00:175::2. When it receives the NA, it flushes its queue and try to send
the initial packet. But instead of sending it, it sends another NS to
resolve fd00:200::fa, which obvioulsy fails, thus the packet is dropped. If
the user sends again the packet, it now uses the right nh (fd00:175::2).

The problem is that ip6_dst_lookup_neigh() uses the rt6i_gateway, which is
:: because the associated route is a connected route, thus it uses the dst
addr of the packet. Let's use rt6_nexthop() to choose the right nh.

Signed-off-by: Nicolas Dichtel <nicolas.dichtel@6wind.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2019-06-26 13:26:08 -07:00
Eric Dumazet
3b52569152 ipv6: fix suspicious RCU usage in rt6_dump_route()
syzbot reminded us that rt6_nh_dump_exceptions() needs to be called
with rcu_read_lock()

net/ipv6/route.c:1593 suspicious rcu_dereference_check() usage!

other info that might help us debug this:

rcu_scheduler_active = 2, debug_locks = 1
2 locks held by syz-executor609/8966:
 #0: 00000000b7dbe288 (rtnl_mutex){+.+.}, at: netlink_dump+0xe7/0xfb0 net/netlink/af_netlink.c:2199
 #1: 00000000f2d87c21 (&(&tb->tb6_lock)->rlock){+...}, at: spin_lock_bh include/linux/spinlock.h:343 [inline]
 #1: 00000000f2d87c21 (&(&tb->tb6_lock)->rlock){+...}, at: fib6_dump_table.isra.0+0x37e/0x570 net/ipv6/ip6_fib.c:533

stack backtrace:
CPU: 0 PID: 8966 Comm: syz-executor609 Not tainted 5.2.0-rc5+ #43
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Call Trace:
 __dump_stack lib/dump_stack.c:77 [inline]
 dump_stack+0x172/0x1f0 lib/dump_stack.c:113
 lockdep_rcu_suspicious+0x153/0x15d kernel/locking/lockdep.c:5250
 fib6_nh_get_excptn_bucket+0x18e/0x1b0 net/ipv6/route.c:1593
 rt6_nh_dump_exceptions+0x45/0x4d0 net/ipv6/route.c:5541
 rt6_dump_route+0x904/0xc50 net/ipv6/route.c:5640
 fib6_dump_node+0x168/0x280 net/ipv6/ip6_fib.c:467
 fib6_walk_continue+0x4a9/0x8e0 net/ipv6/ip6_fib.c:1986
 fib6_walk+0x9d/0x100 net/ipv6/ip6_fib.c:2034
 fib6_dump_table.isra.0+0x38a/0x570 net/ipv6/ip6_fib.c:534
 inet6_dump_fib+0x93c/0xb00 net/ipv6/ip6_fib.c:624
 rtnl_dump_all+0x295/0x490 net/core/rtnetlink.c:3445
 netlink_dump+0x558/0xfb0 net/netlink/af_netlink.c:2244
 __netlink_dump_start+0x5b1/0x7d0 net/netlink/af_netlink.c:2352
 netlink_dump_start include/linux/netlink.h:226 [inline]
 rtnetlink_rcv_msg+0x73d/0xb00 net/core/rtnetlink.c:5182
 netlink_rcv_skb+0x177/0x450 net/netlink/af_netlink.c:2477
 rtnetlink_rcv+0x1d/0x30 net/core/rtnetlink.c:5237
 netlink_unicast_kernel net/netlink/af_netlink.c:1302 [inline]
 netlink_unicast+0x531/0x710 net/netlink/af_netlink.c:1328
 netlink_sendmsg+0x8ae/0xd70 net/netlink/af_netlink.c:1917
 sock_sendmsg_nosec net/socket.c:646 [inline]
 sock_sendmsg+0xd7/0x130 net/socket.c:665
 sock_write_iter+0x27c/0x3e0 net/socket.c:994
 call_write_iter include/linux/fs.h:1872 [inline]
 new_sync_write+0x4d3/0x770 fs/read_write.c:483
 __vfs_write+0xe1/0x110 fs/read_write.c:496
 vfs_write+0x20c/0x580 fs/read_write.c:558
 ksys_write+0x14f/0x290 fs/read_write.c:611
 __do_sys_write fs/read_write.c:623 [inline]
 __se_sys_write fs/read_write.c:620 [inline]
 __x64_sys_write+0x73/0xb0 fs/read_write.c:620
 do_syscall_64+0xfd/0x680 arch/x86/entry/common.c:301
 entry_SYSCALL_64_after_hwframe+0x49/0xbe
RIP: 0033:0x4401b9
Code: 18 89 d0 c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 00 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 0f 83 fb 13 fc ff c3 66 2e 0f 1f 84 00 00 00 00
RSP: 002b:00007ffc8e134978 EFLAGS: 00000246 ORIG_RAX: 0000000000000001
RAX: ffffffffffffffda RBX: 00000000004002c8 RCX: 00000000004401b9
RDX: 000000000000001c RSI: 0000000020000000 RDI: 00

Fixes: 1e47b4837f ("ipv6: Dump route exceptions if requested")
Signed-off-by: Eric Dumazet <edumazet@google.com>
Cc: Stefano Brivio <sbrivio@redhat.com>
Cc: David Ahern <dsahern@gmail.com>
Reviewed-by: Stefano Brivio <sbrivio@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2019-06-26 09:07:50 -07:00
Eiichi Tsukata
b8e8a86337 net/ipv6: Fix misuse of proc_dointvec "skip_notify_on_dev_down"
/proc/sys/net/ipv6/route/skip_notify_on_dev_down assumes given value to be
0 or 1. Use proc_dointvec_minmax instead of proc_dointvec.

Fixes: 7c6bb7d2fa ("net/ipv6: Add knob to skip DELROUTE message ondevice down")
Signed-off-by: Eiichi Tsukata <devel@etsukata.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2019-06-25 12:59:04 -07:00
Stefano Brivio
1e47b4837f ipv6: Dump route exceptions if requested
Since commit 2b760fcf5c ("ipv6: hook up exception table to store dst
cache"), route exceptions reside in a separate hash table, and won't be
found by walking the FIB, so they won't be dumped to userspace on a
RTM_GETROUTE message.

This causes 'ip -6 route list cache' and 'ip -6 route flush cache' to
have no function anymore:

 # ip -6 route get fc00:3::1
 fc00:3::1 via fc00:1::2 dev veth_A-R1 src fc00:1::1 metric 1024 expires 539sec mtu 1400 pref medium
 # ip -6 route get fc00:4::1
 fc00:4::1 via fc00:2::2 dev veth_A-R2 src fc00:2::1 metric 1024 expires 536sec mtu 1500 pref medium
 # ip -6 route list cache
 # ip -6 route flush cache
 # ip -6 route get fc00:3::1
 fc00:3::1 via fc00:1::2 dev veth_A-R1 src fc00:1::1 metric 1024 expires 520sec mtu 1400 pref medium
 # ip -6 route get fc00:4::1
 fc00:4::1 via fc00:2::2 dev veth_A-R2 src fc00:2::1 metric 1024 expires 519sec mtu 1500 pref medium

because iproute2 lists cached routes using RTM_GETROUTE, and flushes them
by listing all the routes, and deleting them with RTM_DELROUTE one by one.

If cached routes are requested using the RTM_F_CLONED flag together with
strict checking, or if no strict checking is requested (and hence we can't
consistently apply filters), look up exceptions in the hash table
associated with the current fib6_info in rt6_dump_route(), and, if present
and not expired, add them to the dump.

We might be unable to dump all the entries for a given node in a single
message, so keep track of how many entries were handled for the current
node in fib6_walker, and skip that amount in case we start from the same
partially dumped node.

When a partial dump restarts, as the starting node might change when
'sernum' changes, we have no guarantee that we need to skip the same
amount of in-node entries. Therefore, we need two counters, and we need to
zero the in-node counter if the node from which the dump is resumed
differs.

Note that, with the current version of iproute2, this only fixes the
'ip -6 route list cache': on a flush command, iproute2 doesn't pass
RTM_F_CLONED and, due to this inconsistency, 'ip -6 route flush cache' is
still unable to fetch the routes to be flushed. This will be addressed in
a patch for iproute2.

To flush cached routes, a procfs entry could be introduced instead: that's
how it works for IPv4. We already have a rt6_flush_exception() function
ready to be wired to it. However, this would not solve the issue for
listing.

Versions of iproute2 and kernel tested:

                    iproute2
kernel             4.14.0   4.15.0   4.19.0   5.0.0   5.1.0    5.1.0, patched
 3.18    list        +        +        +        +       +            +
         flush       +        +        +        +       +            +
 4.4     list        +        +        +        +       +            +
         flush       +        +        +        +       +            +
 4.9     list        +        +        +        +       +            +
         flush       +        +        +        +       +            +
 4.14    list        +        +        +        +       +            +
         flush       +        +        +        +       +            +
 4.15    list
         flush
 4.19    list
         flush
 5.0     list
         flush
 5.1     list
         flush
 with    list        +        +        +        +       +            +
 fix     flush       +        +        +                             +

v7:
  - Explain usage of "skip" counters in commit message (suggested by
    David Ahern)

v6:
  - Rebase onto net-next, use recently introduced nexthop walker
  - Make rt6_nh_dump_exceptions() a separate function (suggested by David
    Ahern)

v5:
  - Use dump_routes and dump_exceptions from filter, ignore NLM_F_MATCH,
    update test results (flushing works with iproute2 < 5.0.0 now)

v4:
  - Split NLM_F_MATCH and strict check handling in separate patches
  - Filter routes using RTM_F_CLONED: if it's not set, only return
    non-cached routes, and if it's set, only return cached routes:
    change requested by David Ahern and Martin Lau. This implies that
    iproute2 needs a separate patch to be able to flush IPv6 cached
    routes. This is not ideal because we can't fix the breakage caused
    by 2b760fcf5c entirely in kernel. However, two years have passed
    since then, and this makes it more tolerable

v3:
  - More descriptive comment about expired exceptions in rt6_dump_route()
  - Swap return values of rt6_dump_route() (suggested by Martin Lau)
  - Don't zero skip_in_node in case we don't dump anything in a given pass
    (also suggested by Martin Lau)
  - Remove check on RTM_F_CLONED altogether: in the current UAPI semantic,
    it's just a flag to indicate the route was cloned, not to filter on
    routes

v2: Add tracking of number of entries to be skipped in current node after
    a partial dump. As we restart from the same node, if not all the
    exceptions for a given node fit in a single message, the dump will
    not terminate, as suggested by Martin Lau. This is a concrete
    possibility, setting up a big number of exceptions for the same route
    actually causes the issue, suggested by David Ahern.

Reported-by: Jianlin Shi <jishi@redhat.com>
Fixes: 2b760fcf5c ("ipv6: hook up exception table to store dst cache")
Signed-off-by: Stefano Brivio <sbrivio@redhat.com>
Reviewed-by: David Ahern <dsahern@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2019-06-24 10:18:49 -07:00
Stefano Brivio
bf9a8a061d ipv6/route: Change return code of rt6_dump_route() for partial node dumps
In the next patch, we are going to add optional dump of exceptions to
rt6_dump_route().

Change the return code of rt6_dump_route() to accomodate partial node
dumps: we might dump multiple routes per node, and might be able to dump
only a given number of them, so fib6_dump_node() will need to know how
many routes have been dumped on partial dump, to restart the dump from the
point where it was interrupted.

Note that fib6_dump_node() is the only caller and already handles all
non-negative return codes as success: those become -1 to signal that we're
done with the node. If we fail, return 0, as we were unable to dump the
single route in the node, but we're not done with it.

Signed-off-by: Stefano Brivio <sbrivio@redhat.com>
Reviewed-by: David Ahern <dsahern@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2019-06-24 10:18:49 -07:00
Stefano Brivio
3401bfb163 ipv6/route: Don't match on fc_nh_id if not set in ip6_route_del()
If fc_nh_id isn't set, we shouldn't try to match against it. This
actually matters just for the RTF_CACHE below (where this case is
already handled): if iproute2 gets a route exception and tries to
delete it, it won't reference it by fc_nh_id, even if a nexthop
object might be associated to the originating route.

Fixes: 5b98324ebe ("ipv6: Allow routes to use nexthop objects")
Signed-off-by: Stefano Brivio <sbrivio@redhat.com>
Reviewed-by: David Ahern <dsahern@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2019-06-24 10:18:49 -07:00
Wei Wang
7d9e5f4221 ipv6: convert major tx path to use RT6_LOOKUP_F_DST_NOREF
For tx path, in most cases, we still have to take refcnt on the dst
cause the caller is caching the dst somewhere. But it still is
beneficial to make use of RT6_LOOKUP_F_DST_NOREF flag while doing the
route lookup. It is cause this flag prevents manipulating refcnt on
net->ipv6.ip6_null_entry when doing fib6_rule_lookup() to traverse each
routing table. The null_entry is a shared object and constant updates on
it cause false sharing.

We converted the current major lookup function ip6_route_output_flags()
to make use of RT6_LOOKUP_F_DST_NOREF.

Together with the change in the rx path, we see noticable performance
boost:
I ran synflood tests between 2 hosts under the same switch. Both hosts
have 20G mlx NIC, and 8 tx/rx queues.
Sender sends pure SYN flood with random src IPs and ports using trafgen.
Receiver has a simple TCP listener on the target port.
Both hosts have multiple custom rules:
- For incoming packets, only local table is traversed.
- For outgoing packets, 3 tables are traversed to find the route.
The packet processing rate on the receiver is as follows:
- Before the fix: 3.78Mpps
- After the fix:  5.50Mpps

Signed-off-by: Wei Wang <weiwan@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2019-06-23 13:24:17 -07:00
Wei Wang
67f415dd29 ipv6: convert rx data path to not take refcnt on dst
ip6_route_input() is the key function to do the route lookup in the
rx data path. All the callers to this function are already holding rcu
lock. So it is fairly easy to convert it to not take refcnt on the dst:
We pass in flag RT6_LOOKUP_F_DST_NOREF and do skb_dst_set_noref().
This saves a few atomic inc or dec operations and should boost
performance overall.
This also makes the logic more aligned with v4.

Signed-off-by: Wei Wang <weiwan@google.com>
Acked-by: Eric Dumazet <edumazet@google.com>
Acked-by: Mahesh Bandewar <maheshb@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2019-06-23 13:24:17 -07:00
Wei Wang
74109218b0 ipv6: initialize rt6->rt6i_uncached in all pre-allocated dst entries
Initialize rt6->rt6i_uncached on the following pre-allocated dsts:
net->ipv6.ip6_null_entry
net->ipv6.ip6_prohibit_entry
net->ipv6.ip6_blk_hole_entry

This is a preparation patch for later commits to be able to distinguish
dst entries in uncached list by doing:
!list_empty(rt6->rt6i_uncached)

Signed-off-by: Wei Wang <weiwan@google.com>
Acked-by: Eric Dumazet <edumazet@google.com>
Acked-by: Mahesh Bandewar <maheshb@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2019-06-23 13:24:17 -07:00
Wei Wang
0e09edcce7 ipv6: introduce RT6_LOOKUP_F_DST_NOREF flag in ip6_pol_route()
This new flag is to instruct the route lookup function to not take
refcnt on the dst entry. The user which does route lookup with this flag
must properly use rcu protection.
ip6_pol_route() is the major route lookup function for both tx and rx
path.
In this function:
Do not take refcnt on dst if RT6_LOOKUP_F_DST_NOREF flag is set, and
directly return the route entry. The caller should be holding rcu lock
when using this flag, and decide whether to take refcnt or not.

One note on the dst cache in the uncached_list:
As uncached_list does not consume refcnt, one refcnt is always returned
back to the caller even if RT6_LOOKUP_F_DST_NOREF flag is set.
Uncached dst is only possible in the output path. So in such call path,
caller MUST check if the dst is in the uncached_list before assuming
that there is no refcnt taken on the returned dst.

Signed-off-by: Wei Wang <weiwan@google.com>
Acked-by: Eric Dumazet <edumazet@google.com>
Acked-by: Mahesh Bandewar <maheshb@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2019-06-23 13:24:17 -07:00
Ido Schimmel
9eee3b4913 ipv6: Error when route does not have any valid nexthops
When user space sends invalid information in RTA_MULTIPATH, the nexthop
list in ip6_route_multipath_add() is empty and 'rt_notif' is set to
NULL.

The code that emits the in-kernel notifications does not check for this
condition, which results in a NULL pointer dereference [1].

Fix this by bailing earlier in the function if the parsed nexthop list
is empty. This is consistent with the corresponding IPv4 code.

v2:
* Check if parsed nexthop list is empty and bail with extack set

[1]
kasan: CONFIG_KASAN_INLINE enabled
kasan: GPF could be caused by NULL-ptr deref or user memory access
general protection fault: 0000 [#1] PREEMPT SMP KASAN
CPU: 0 PID: 9190 Comm: syz-executor149 Not tainted 5.2.0-rc5+ #38
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS
Google 01/01/2011
RIP: 0010:call_fib6_multipath_entry_notifiers+0xd1/0x1a0
net/ipv6/ip6_fib.c:396
Code: 8b b5 30 ff ff ff 48 c7 85 68 ff ff ff 00 00 00 00 48 c7 85 70 ff ff
ff 00 00 00 00 89 45 88 4c 89 e0 48 c1 e8 03 4c 89 65 80 <42> 80 3c 28 00
0f 85 9a 00 00 00 48 b8 00 00 00 00 00 fc ff df 4d
RSP: 0018:ffff88809788f2c0 EFLAGS: 00010246
RAX: 0000000000000000 RBX: 1ffff11012f11e59 RCX: 00000000ffffffff
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000
RBP: ffff88809788f390 R08: ffff88809788f8c0 R09: 000000000000000c
R10: ffff88809788f5d8 R11: ffff88809788f527 R12: 0000000000000000
R13: dffffc0000000000 R14: ffff88809788f8c0 R15: ffffffff89541d80
FS:  000055555632c880(0000) GS:ffff8880ae800000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000000020000080 CR3: 000000009ba7c000 CR4: 00000000001406f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
  ip6_route_multipath_add+0xc55/0x1490 net/ipv6/route.c:5094
  inet6_rtm_newroute+0xed/0x180 net/ipv6/route.c:5208
  rtnetlink_rcv_msg+0x463/0xb00 net/core/rtnetlink.c:5219
  netlink_rcv_skb+0x177/0x450 net/netlink/af_netlink.c:2477
  rtnetlink_rcv+0x1d/0x30 net/core/rtnetlink.c:5237
  netlink_unicast_kernel net/netlink/af_netlink.c:1302 [inline]
  netlink_unicast+0x531/0x710 net/netlink/af_netlink.c:1328
  netlink_sendmsg+0x8ae/0xd70 net/netlink/af_netlink.c:1917
  sock_sendmsg_nosec net/socket.c:646 [inline]
  sock_sendmsg+0xd7/0x130 net/socket.c:665
  ___sys_sendmsg+0x803/0x920 net/socket.c:2286
  __sys_sendmsg+0x105/0x1d0 net/socket.c:2324
  __do_sys_sendmsg net/socket.c:2333 [inline]
  __se_sys_sendmsg net/socket.c:2331 [inline]
  __x64_sys_sendmsg+0x78/0xb0 net/socket.c:2331
  do_syscall_64+0xfd/0x680 arch/x86/entry/common.c:301
  entry_SYSCALL_64_after_hwframe+0x49/0xbe
RIP: 0033:0x4401f9
Code: 18 89 d0 c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 00 48 89 f8 48 89 f7
48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff
ff 0f 83 fb 13 fc ff c3 66 2e 0f 1f 84 00 00 00 00
RSP: 002b:00007ffc09fd0028 EFLAGS: 00000246 ORIG_RAX: 000000000000002e
RAX: ffffffffffffffda RBX: 00000000004002c8 RCX: 00000000004401f9
RDX: 0000000000000000 RSI: 0000000020000080 RDI: 0000000000000003
RBP: 00000000006ca018 R08: 0000000000000000 R09: 00000000004002c8
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000401a80
R13: 0000000000401b10 R14: 0000000000000000 R15: 0000000000000000

Reported-by: syzbot+382566d339d52cd1a204@syzkaller.appspotmail.com
Fixes: ebee3cad83 ("ipv6: Add IPv6 multipath notifications for add / replace")
Signed-off-by: Ido Schimmel <idosch@mellanox.com>
Reviewed-by: Jiri Pirko <jiri@mellanox.com>
Reviewed-by: David Ahern <dsahern@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2019-06-22 16:50:35 -07:00
David S. Miller
92ad6325cb Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net
Minor SPDX change conflict.

Signed-off-by: David S. Miller <davem@davemloft.net>
2019-06-22 08:59:24 -04:00
David Ahern
c7036d97ac ipv6: Default fib6_type to RTN_UNICAST when not set
A user reported that routes are getting installed with type 0 (RTN_UNSPEC)
where before the routes were RTN_UNICAST. One example is from accel-ppp
which apparently still uses the ioctl interface and does not set
rtmsg_type. Another is the netlink interface where ipv6 does not require
rtm_type to be set (v4 does). Prior to the commit in the Fixes tag the
ipv6 stack converted type 0 to RTN_UNICAST, so restore that behavior.

Fixes: e8478e80e5 ("net/ipv6: Save route type in rt6_info")
Signed-off-by: David Ahern <dsahern@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2019-06-19 17:14:05 -04:00
Ido Schimmel
2881fd61b6 ipv6: Add IPv6 multipath notification for route delete
If all the nexthops of a multipath route are being deleted, send one
notification for the entire route, instead of one per-nexthop.

Signed-off-by: Ido Schimmel <idosch@mellanox.com>
Acked-by: Jiri Pirko <jiri@mellanox.com>
Reviewed-by: David Ahern <dsahern@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2019-06-18 09:45:36 -07:00
Ido Schimmel
ebee3cad83 ipv6: Add IPv6 multipath notifications for add / replace
Emit a notification when a multipath routes is added or replace.

Note that unlike the replace notifications sent from fib6_add_rt2node(),
it is possible we are sending a 'FIB_EVENT_ENTRY_REPLACE' when a route
was merely added and not replaced.

Signed-off-by: Ido Schimmel <idosch@mellanox.com>
Acked-by: Jiri Pirko <jiri@mellanox.com>
Reviewed-by: David Ahern <dsahern@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2019-06-18 09:45:36 -07:00
David Ahern
5b98324ebe ipv6: Allow routes to use nexthop objects
Add support for RTA_NH_ID attribute to allow a user to specify a
nexthop id to use with a route. fc_nh_id is added to fib6_config to
hold the value passed in the RTA_NH_ID attribute. If a nexthop id
is given, the gateway, device, encap and multipath attributes can
not be set.

Update ip6_route_del to check metric and protocol before nexthop
specs. If fc_nh_id is set, then it must match the id in the route
entry. Since IPv6 allows delete of a cached entry (an exception),
add ip6_del_cached_rt_nh to cycle through all of the fib6_nh in
a fib entry if it is using a nexthop.

Signed-off-by: David Ahern <dsahern@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2019-06-10 10:44:57 -07:00
David Ahern
2d44234bf9 ipv6: Handle all fib6_nh in a nexthop in mtu updates
Use nexthop_for_each_fib6_nh to call fib6_nh_mtu_change for each
fib6_nh in a nexthop for rt6_mtu_change_route. For __ip6_rt_update_pmtu,
we need to find the nexthop that correlates to the device and gateway
in the rt6_info.

Signed-off-by: David Ahern <dsahern@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2019-06-10 10:44:56 -07:00
David Ahern
49d5b8ef20 ipv6: Handle all fib6_nh in a nexthop in rt6_do_redirect
Use nexthop_for_each_fib6_nh and fib6_nh_find_match to find the
fib6_nh in a nexthop that correlates to the device and gateway
in the rt6_info.

Signed-off-by: David Ahern <dsahern@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2019-06-10 10:44:56 -07:00
David Ahern
c55c89884d ipv6: Handle all fib6_nh in a nexthop in __ip6_route_redirect
Add a hook in __ip6_route_redirect to handle a nexthop struct in a
fib6_info. Use nexthop_for_each_fib6_nh and fib6_nh_redirect_match
to call ip6_redirect_nh_match for each fib6_nh looking for a match.

Signed-off-by: David Ahern <dsahern@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2019-06-10 10:44:56 -07:00
David Ahern
e659ba31d8 ipv6: Handle all fib6_nh in a nexthop in exception handling
Add a hook in rt6_flush_exceptions, rt6_remove_exception_rt,
rt6_update_exception_stamp_rt, and rt6_age_exceptions to handle
nexthop struct in a fib6_info.

Signed-off-by: David Ahern <dsahern@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2019-06-10 10:44:56 -07:00
David Ahern
2c170e0753 ipv6: Handle all fib6_nh in a nexthop in fib6_info_uses_dev
Add a hook in fib6_info_uses_dev to handle nexthop struct in a fib6_info.

Signed-off-by: David Ahern <dsahern@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2019-06-10 10:44:56 -07:00
David Ahern
a1b7a1f06c ipv6: Handle all fib6_nh in a nexthop in rt6_nlmsg_size
Add a hook in rt6_nlmsg_size to handle nexthop struct in a fib6_info.
rt6_nh_nlmsg_size is used to sum the space needed for all nexthops in
the fib entry.

Signed-off-by: David Ahern <dsahern@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2019-06-10 10:44:56 -07:00
David Ahern
17a5984eee ipv6: Handle all fib6_nh in a nexthop in __find_rr_leaf
Add a hook in __find_rr_leaf to handle nexthop struct in a fib6_info.
nexthop_for_each_fib6_nh is used to walk each fib6_nh in a nexthop and
call find_match. On a match, use the fib6_nh saved in the callback arg
to setup fib6_result.

Signed-off-by: David Ahern <dsahern@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2019-06-10 10:44:56 -07:00
David Ahern
962b680383 ipv6: Handle all fib6_nh in a nexthop in rt6_device_match
Add a hook in rt6_device_match to handle nexthop struct in a fib6_info.
The new rt6_nh_dev_match uses nexthop_for_each_fib6_nh to walk each
fib6_nh in a nexthop and call __rt6_device_match. On match,
rt6_nh_dev_match returns the fib6_nh and rt6_device_match uses it to
setup fib6_result.

Signed-off-by: David Ahern <dsahern@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2019-06-10 10:44:56 -07:00
David S. Miller
a6cdeeb16b Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net
Some ISDN files that got removed in net-next had some changes
done in mainline, take the removals.

Signed-off-by: David S. Miller <davem@davemloft.net>
2019-06-07 11:00:14 -07:00
Colin Ian King
4daa95af7f ipv6: fix spelling mistake: "wtih" -> "with"
There is a spelling mistake in a NL_SET_ERR_MSG message. Fix it.

Signed-off-by: Colin Ian King <colin.king@canonical.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2019-06-06 10:37:28 -07:00
David Ahern
f88d8ea67f ipv6: Plumb support for nexthop object in a fib6_info
Add struct nexthop and nh_list list_head to fib6_info. nh_list is the
fib6_info side of the nexthop <-> fib_info relationship. Since a fib6_info
referencing a nexthop object can not have 'sibling' entries (the old way
of doing multipath routes), the nh_list is a union with fib6_siblings.

Add f6i_list list_head to 'struct nexthop' to track fib6_info entries
using a nexthop instance. Update __remove_nexthop_fib to walk f6_list
and delete fib entries using the nexthop.

Add a few nexthop helpers for use when a nexthop is added to fib6_info:
- nexthop_fib6_nh - return first fib6_nh in a nexthop object
- fib6_info_nh_dev moved to nexthop.h and updated to use nexthop_fib6_nh
  if the fib6_info references a nexthop object
- nexthop_path_fib6_result - similar to ipv4, select a path within a
  multipath nexthop object. If the nexthop is a blackhole, set
  fib6_result type to RTN_BLACKHOLE, and set the REJECT flag

Update the fib6_info references to check for nh and take a different path
as needed:
- rt6_qualify_for_ecmp - if a fib entry uses a nexthop object it can NOT
  be coalesced with other fib entries into a multipath route
- rt6_duplicate_nexthop - use nexthop_cmp if either fib6_info references
  a nexthop
- addrconf (host routes), RA's and info entries (anything configured via
  ndisc) does not use nexthop objects
- fib6_info_destroy_rcu - put reference to nexthop object
- fib6_purge_rt - drop fib6_info from f6i_list
- fib6_select_path - update to use the new nexthop_path_fib6_result when
  fib entry uses a nexthop object
- rt6_device_match - update to catch use of nexthop object as a blackhole
  and set fib6_type and flags.
- ip6_route_info_create - don't add space for fib6_nh if fib entry is
  going to reference a nexthop object, take a reference to nexthop object,
  disallow use of source routing
- rt6_nlmsg_size - add space for RTA_NH_ID
- add rt6_fill_node_nexthop to add nexthop data on a dump

As with ipv4, most of the changes push existing code into the else branch
of whether the fib entry uses a nexthop object.

Update the nexthop code to walk f6i_list on a nexthop deleted to remove
fib entries referencing it.

Signed-off-by: David Ahern <dsahern@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2019-06-04 19:26:50 -07:00
David Ahern
7dd73168e2 ipv6: Always allocate pcpu memory in a fib6_nh
A recent commit had an unintended side effect with reject routes:
rt6i_pcpu is expected to always be initialized for all fib6_info except
the null entry. The commit mentioned below skips it for reject routes
and ends up leaking references to the loopback device. For example,

    ip netns add foo
    ip -netns foo li set lo up
    ip -netns foo -6 ro add blackhole 2001:db8:1::1
    ip netns exec foo ping6 2001:db8:1::1
    ip netns del foo

ends up spewing:
    unregister_netdevice: waiting for lo to become free. Usage count = 3

The fib_nh_common_init is not needed for reject routes (no ipv4 caching
or encaps), so move the alloc_percpu_gfp after it and adjust the goto label.

Fixes: f40b6ae2b6 ("ipv6: Move pcpu cached routes to fib6_nh")
Signed-off-by: David Ahern <dsahern@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2019-06-04 14:54:59 -07:00
Eric Dumazet
c353071ad0 ipv6: use this_cpu_read() in rt6_get_pcpu_route()
this_cpu_read(*X) is faster than *this_cpu_ptr(X)

Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2019-06-03 15:06:36 -07:00
David S. Miller
b4b12b0d2f Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net
The phylink conflict was between a bug fix by Russell King
to make sure we have a consistent PHY interface mode, and
a change in net-next to pull some code in phylink_resolve()
into the helper functions phylink_mac_link_{up,down}()

On the dp83867 side it's mostly overlapping changes, with
the 'net' side removing a condition that was supposed to
trigger for RGMII but because of how it was coded never
actually could trigger.

Signed-off-by: David S. Miller <davem@davemloft.net>
2019-05-31 10:49:43 -07:00
Linus Torvalds
2f4c533499 SPDX update for 5.2-rc3, round 1
Here is another set of reviewed patches that adds SPDX tags to different
 kernel files, based on a set of rules that are being used to parse the
 comments to try to determine that the license of the file is
 "GPL-2.0-or-later" or "GPL-2.0-only".  Only the "obvious" versions of
 these matches are included here, a number of "non-obvious" variants of
 text have been found but those have been postponed for later review and
 analysis.
 
 There is also a patch in here to add the proper SPDX header to a bunch
 of Kbuild files that we have missed in the past due to new files being
 added and forgetting that Kbuild uses two different file names for
 Makefiles.  This issue was reported by the Kbuild maintainer.
 
 These patches have been out for review on the linux-spdx@vger mailing
 list, and while they were created by automatic tools, they were
 hand-verified by a bunch of different people, all whom names are on the
 patches are reviewers.
 
 Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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Merge tag 'spdx-5.2-rc3-1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core

Pull yet more SPDX updates from Greg KH:
 "Here is another set of reviewed patches that adds SPDX tags to
  different kernel files, based on a set of rules that are being used to
  parse the comments to try to determine that the license of the file is
  "GPL-2.0-or-later" or "GPL-2.0-only". Only the "obvious" versions of
  these matches are included here, a number of "non-obvious" variants of
  text have been found but those have been postponed for later review
  and analysis.

  There is also a patch in here to add the proper SPDX header to a bunch
  of Kbuild files that we have missed in the past due to new files being
  added and forgetting that Kbuild uses two different file names for
  Makefiles. This issue was reported by the Kbuild maintainer.

  These patches have been out for review on the linux-spdx@vger mailing
  list, and while they were created by automatic tools, they were
  hand-verified by a bunch of different people, all whom names are on
  the patches are reviewers"

* tag 'spdx-5.2-rc3-1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core: (82 commits)
  treewide: Add SPDX license identifier - Kbuild
  treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 225
  treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 224
  treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 223
  treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 222
  treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 221
  treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 220
  treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 218
  treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 217
  treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 216
  treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 215
  treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 214
  treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 213
  treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 211
  treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 210
  treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 209
  treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 207
  treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 206
  treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 203
  treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 201
  ...
2019-05-31 08:34:32 -07:00
Thomas Gleixner
2874c5fd28 treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 152
Based on 1 normalized pattern(s):

  this program is free software you can redistribute it and or modify
  it under the terms of the gnu general public license as published by
  the free software foundation either version 2 of the license or at
  your option any later version

extracted by the scancode license scanner the SPDX license identifier

  GPL-2.0-or-later

has been chosen to replace the boilerplate/reference in 3029 file(s).

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Allison Randal <allison@lohutok.net>
Cc: linux-spdx@vger.kernel.org
Link: https://lkml.kernel.org/r/20190527070032.746973796@linutronix.de
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-05-30 11:26:32 -07:00
David Ahern
0fa6efc547 ipv6: Refactor ip6_route_del for cached routes
Move the removal of cached routes to a helper, ip6_del_cached_rt, that
can be invoked per nexthop. Rename the existig ip6_del_cached_rt to
__ip6_del_cached_rt since it is called by ip6_del_cached_rt.

Signed-off-by: David Ahern <dsahern@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2019-05-24 13:26:44 -07:00
David Ahern
1cf844c747 ipv6: Make fib6_nh optional at the end of fib6_info
Move fib6_nh to the end of fib6_info and make it an array of
size 0. Pass a flag to fib6_info_alloc indicating if the
allocation needs to add space for a fib6_nh.

The current code path always has a fib6_nh allocated with a
fib6_info; with nexthop objects they will be separate.

Signed-off-by: David Ahern <dsahern@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2019-05-24 13:26:44 -07:00
David Ahern
cc5c073a69 ipv6: Move exception bucket to fib6_nh
Similar to the pcpu routes exceptions are really per nexthop, so move
rt6i_exception_bucket from fib6_info to fib6_nh.

To avoid additional increases to the size of fib6_nh for a 1-bit flag,
use the lowest bit in the allocated memory pointer for the flushed flag.
Add helpers for retrieving the bucket pointer to mask off the flag.

The cleanup of the exception bucket is moved to fib6_nh_release.

fib6_nh_flush_exceptions can now be called from 2 contexts:
1. deleting a fib entry
2. deleting a fib6_nh

For 1., fib6_nh_flush_exceptions is called for a specific fib6_info that
is getting deleted. All exceptions in the cache using the entry are
deleted. For 2, the fib6_nh itself is getting destroyed so
fib6_nh_flush_exceptions is called for a NULL fib6_info which means
flush all entries.

The pmtu.sh selftest exercises the affected code paths - from creating
exceptions to cleaning them up on device delete. All tests pass without
any rcu locking or memleak warnings.

Signed-off-by: David Ahern <dsahern@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2019-05-24 13:26:44 -07:00
David Ahern
c0b220cf7d ipv6: Refactor exception functions
Before moving exception bucket from fib6_info to fib6_nh, refactor
rt6_flush_exceptions, rt6_remove_exception_rt, rt6_mtu_change_route,
and rt6_update_exception_stamp_rt. In all 3 cases, move the primary
logic into a new helper that starts with fib6_nh_. The latter 3
functions still take a fib6_info; this will be changed to fib6_nh
in the next patch.

In the case of rt6_mtu_change_route, move the fib6_metric_locked
out as a standalone check - no need to call the new function if
the fib entry has the mtu locked. Also, add fib6_info to
rt6_mtu_change_arg as a way of passing the fib entry to the new
helper.

No functional change intended. The goal here is to make the next
patch easier to review by moving existing lookup logic for each to
new helpers.

Signed-off-by: David Ahern <dsahern@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2019-05-24 13:26:44 -07:00
David Ahern
f40b6ae2b6 ipv6: Move pcpu cached routes to fib6_nh
rt6_info are specific instances of a fib entry and are tied to a
device and gateway - ie., a nexthop. Before nexthop objects, IPv6 fib
entries have separate fib6_info for each nexthop in a multipath route,
so the location of the pcpu cache in the fib6_info struct worked.
However, with nexthop objects a fib6_info can point to a set of nexthops
(yet another alignment of ipv6 with ipv4). Accordingly, the pcpu
cache needs to be moved to the fib6_nh struct so the cached entries
are local to the nexthop specification used to create the rt6_info.

Initialization and free of the pcpu entries moved to fib6_nh_init and
fib6_nh_release.

Change in location only, from fib6_info down to fib6_nh; no other
functional change intended.

Signed-off-by: David Ahern <dsahern@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2019-05-24 13:26:44 -07:00
David Ahern
31680ac265 ipv6: Fix redirect with VRF
IPv6 redirect is broken for VRF. __ip6_route_redirect walks the FIB
entries looking for an exact match on ifindex. With VRF the flowi6_oif
is updated by l3mdev_update_flow to the l3mdev index and the
FLOWI_FLAG_SKIP_NH_OIF set in the flags to tell the lookup to skip the
device match. For redirects the device match is requires so use that
flag to know when the oif needs to be reset to the skb device index.

Fixes: ca254490c8 ("net: Add VRF support to IPv6 stack")
Signed-off-by: David Ahern <dsahern@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2019-05-22 17:58:21 -07:00
David Ahern
75425657fe net: Set strict_start_type for routes and rules
New userspace on an older kernel can send unknown and unsupported
attributes resulting in an incompelete config which is almost
always wrong for routing (few exceptions are passthrough settings
like the protocol that installed the route).

Set strict_start_type in the policies for IPv4 and IPv6 routes and
rules to detect new, unsupported attributes and fail the route add.

Signed-off-by: David Ahern <dsahern@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2019-05-22 17:50:24 -07:00
David Ahern
19a3b7eea4 ipv6: export function to send route updates
Add fib6_rt_update to send RTM_NEWROUTE with NLM_F_REPLACE set. This
helper will be used by the nexthop code to notify userspace of routes
that are impacted when a nexthop config is updated via replace.

This notification is needed for legacy apps that do not understand
the new nexthop object. Apps that are nexthop aware can use the
RTA_NH_ID attribute in the route notification to just ignore it.

In the future this should be wrapped in a sysctl to allow OS'es that
are fully updated to avoid the notificaton storm.

Signed-off-by: David Ahern <dsahern@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2019-05-22 17:48:43 -07:00
Wei Wang
510e2ceda0 ipv6: fix src addr routing with the exception table
When inserting route cache into the exception table, the key is
generated with both src_addr and dest_addr with src addr routing.
However, current logic always assumes the src_addr used to generate the
key is a /128 host address. This is not true in the following scenarios:
1. When the route is a gateway route or does not have next hop.
   (rt6_is_gw_or_nonexthop() == false)
2. When calling ip6_rt_cache_alloc(), saddr is passed in as NULL.
This means, when looking for a route cache in the exception table, we
have to do the lookup twice: first time with the passed in /128 host
address, second time with the src_addr stored in fib6_info.

This solves the pmtu discovery issue reported by Mikael Magnusson where
a route cache with a lower mtu info is created for a gateway route with
src addr. However, the lookup code is not able to find this route cache.

Fixes: 2b760fcf5c ("ipv6: hook up exception table to store dst cache")
Reported-by: Mikael Magnusson <mikael.kernel@lists.m7n.se>
Bisected-by: David Ahern <dsahern@gmail.com>
Signed-off-by: Wei Wang <weiwan@google.com>
Cc: Martin Lau <kafai@fb.com>
Cc: Eric Dumazet <edumazet@google.com>
Acked-by: Martin KaFai Lau <kafai@fb.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2019-05-16 14:30:53 -07:00
Eric Dumazet
61fb0d0168 ipv6: prevent possible fib6 leaks
At ipv6 route dismantle, fib6_drop_pcpu_from() is responsible
for finding all percpu routes and set their ->from pointer
to NULL, so that fib6_ref can reach its expected value (1).

The problem right now is that other cpus can still catch the
route being deleted, since there is no rcu grace period
between the route deletion and call to fib6_drop_pcpu_from()

This can leak the fib6 and associated resources, since no
notifier will take care of removing the last reference(s).

I decided to add another boolean (fib6_destroying) instead
of reusing/renaming exception_bucket_flushed to ease stable backports,
and properly document the memory barriers used to implement this fix.

This patch has been co-developped with Wei Wang.

Fixes: 93531c6743 ("net/ipv6: separate handling of FIB entries from dst based routes")
Signed-off-by: Eric Dumazet <edumazet@google.com>
Reported-by: syzbot <syzkaller@googlegroups.com>
Cc: Wei Wang <weiwan@google.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Martin Lau <kafai@fb.com>
Acked-by: Wei Wang <weiwan@google.com>
Acked-by: Martin KaFai Lau <kafai@fb.com>
Reviewed-by: David Ahern <dsahern@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2019-05-16 12:21:00 -07:00